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Find video protocols related to scientific articles indexed in Pubmed.
Efficient multiband and broadband cross polarization converters based on slotted L-shaped nanoantennas.
Opt Express
PUBLISHED: 11-18-2014
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In this paper, we presented highly efficient reflective cross polarization converters based on metamaterials operating in the infrared regime, which are composed of a dielectric spacer sandwiched between slotted L-shaped metallic nanoantennas and a ground plane. The proposed polarization converters can convert a linearly polarized wave to its cross polarized wave with high polarization conversion ratio (> 0.95) over multiple / broad frequency bands. The resulting multi-band and broadband operations are induced by the localized mode hybridizations between the slot and the original metallic nanoantenna. Furthermore, the performance of the proposed converters under different incident angles is also explored. It is found that the first broad band (or the first two resonant frequencies) of the proposed broadband (or multi-band) converters appears to be independent of the incident angle (up to 47°).
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[Clinical characteristics of whooping cough in neonates and antimicrobial resistance of the pathogenic bacteria].
Zhongguo Dang Dai Er Ke Za Zhi
PUBLISHED: 10-26-2014
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To study the clinical characteristics of whooping cough in neonates and the antimicrobial resistance of the bacterial isolates.
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In-syringe dispersive solid phase extraction: a novel format for electrospun fiber based microextraction.
Analyst
PUBLISHED: 10-16-2014
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A novel in-syringe dispersive solid phase extraction (dSPE) system using electrospun silica fibers as adsorbents has been developed in the current work. A few milligrams of electrospun silica fibers were incubated in sample solution in the barrel of a syringe for microextraction assisted by vortex. Due to the benefit of dispersion and the high mass transfer rate of the sub-microscale electrospun silica fibers, the extraction equilibrium was achieved in a very short time (less than 1 min). Moreover, thanks to the long fibrous properties of electrospun fibers, the separation of the adsorbent from sample solution was easily achieved by pushing out the sample solution which therefore simplified the sample pretreatment procedure. Besides, the analytical throughput was largely increased by using a multi-syringe plate to perform the extraction experiment. The performance of the in-syringe dSPE device was evaluated by extraction of endogenous cytokinins from plant tissue samples based on the hydrophilic interaction. Six endogenous cytokinins in 20 mg of Oryza sativa L. (O. sativa) leaves were successfully determined under optimized conditions using in-syringe dSPE combined with liquid chromatography-mass spectrometry analysis. The results demonstrated that the in-syringe dSPE method was a rapid and high-throughput strategy for the extraction of target compounds, which has great potential in microscale sample pretreatment using electrospun fibers.
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Radiofrequency ablation of hepatocellular carcinoma in elderly patients fitting the Milan criteria: A single centre with 13 years experience.
Int J Hyperthermia
PUBLISHED: 10-14-2014
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Abstract Purpose: The aim of this study was to evaluate the safety and outcomes of radiofrequency ablation (RFA) in treating elderly patients with hepatocellular carcinoma (HCC).
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Risk factors for bunyavirus-associated severe Fever with thrombocytopenia syndrome, china.
PLoS Negl Trop Dis
PUBLISHED: 10-01-2014
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Severe fever with thrombocytopenia syndrome (SFTS) is an emerging disease that is caused by a novel bunyavirus, referred to as SFTS virus. During January 2011 to December 2011 we conducted a case-control study in Henan, Hubei and Shandong Provinces of China to determine the risk factors for SFTS.
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piRNA identification based on motif discovery.
Mol Biosyst
PUBLISHED: 09-19-2014
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Piwi-interacting RNA (piRNA) is a class of small non-coding RNAs about 24 to 32 nucleotides long, associated with PIWI proteins, which are involved in germline development, transposon silencing, and epigenetic regulation. Identification of piRNA loci on the genome is very useful for further studies in the biogenesis and function of piRNAs. To accomplish this, we applied the computational biology tool Teiresias to identify motifs of variable length appearing frequently in mouse piRNA and non-piRNA sequences, respectively, and then proposed an algorithm for piRNA identification based on motif discovery, termed "Pibomd" by using these sequence motifs as features in the Support Vector Machine (SVM) algorithm, a sensitivity of 91.48% and a specificity of 89.76% on a mouse test dataset could be achieved, much better results than those reported in previously published algorithms. We also trained an unbalanced SVM classifier (named as "Asym-Pibomd") that provided a higher specificity (96.2%) and a lower sensitivity (72.68%) than Pibomd. Inspite of the predicted ACC being less than that of Pibomd, the predicted ACC (84.44%) of Asym-Pibomd is about ten percent more than that obtained using the k-mer method. Further analysis of the motif positions on the piRNA sequences showed that the piRNA sequences may contain information at the 5'- and/or 3'-end recognized by the piRNA processing apparatus of actual piRNA precursors. Furthermore, this prediction method can be found on a user-friendly web server found at .
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Soft spots and their structural signature in a metallic glass.
Proc. Natl. Acad. Sci. U.S.A.
PUBLISHED: 09-16-2014
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In a 3D model mimicking realistic Cu64Zr36 metallic glass, we uncovered a direct link between the quasi-localized low-frequency vibrational modes and the local atomic packing structure. We also demonstrate that quasi-localized soft modes correlate strongly with fertile sites for shear transformations: geometrically unfavored motifs constitute the most flexible local environments that encourage soft modes and high propensity for shear transformations, whereas local configurations preferred in this alloy, i.e., the full icosahedra (around Cu) and Z16 Kasper polyhedra (around Zr), contribute the least.
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Nitrogen loss through anaerobic ammonium oxidation coupled to iron reduction from paddy soils in a chronosequence.
Environ. Sci. Technol.
PUBLISHED: 09-05-2014
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Anaerobic ammonium oxidation coupled to iron(III) reduction (termed Feammox) with dinitrogen, nitrite, or nitrate as the end-product is a recently discovered process of nitrogen cycling. However, Feammox has not been described in paddy soils, which are rich in iron(III) oxides and subjected to intensive nitrogen fertilization. Here, evidence for Feammox in a paddy soil chronosequence with a gradient of microbially reducible iron(III) levels was obtained in Southern China using (15)N-labeled ammonium-based isotopic tracing and acetylene inhibition techniques. Our study demonstrated the occurrence of Feammox in the chronosequence, and direct dinitrogen production was shown to be the dominant Feammox pathway. Within the chronosequence, three paddy soils with higher microbially reducible iron(III) levels had higher Feammox rates (ranged from 0.17 to 0.59 mg N kg(-1) d(-1)) compared to an uncultivated soil (0.04 mg N kg(-1) d(-1)). It is estimated that a loss of 7.8-61 kg N ha(-1) year(-1) is associated with Feammox in the examined paddy soils. Overall, we discover that rice cultivation could enrich microbially reducible iron(III), accelerate Feammox reaction and thus fuel nitrogen loss from soils, and suggest that Feammox could be a potentially important pathway for nitrogen loss in paddy soils.
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Changes of Serum Osteocalcin, Calcium, and Potassium in a Rat Model of Type 2 Diabetes.
Cell Biochem. Biophys.
PUBLISHED: 09-04-2014
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Changes in serum levels of calcium (Ca), phosphorus (P), Ca phosphate, alkaline phosphatase (AKP), and osteocalcin (BGP) were assessed in a model of type 2 diabetes in 8-weeks-old Sprague-Dawley rats. Throughout the study, the animals in Group A consumed high-carbohydrate, high-fat diet and were administered two intraperitoneal injections of streptozocin (STZ) at 4 (25 mg/kg) and 8 (40 mg/kg) weeks after diet initiation. Animals in Group B received similar diet but intraperitoneal injections with citrate buffer. The control group rats (Group C) were fed normal diet and received citrate buffer injections. The Ca levels in Group A were significantly decreased at 12 and 16 weeks, while P levels were significantly lower at 8, 12, and 16 weeks after the first STZ injection (p < 0.05 vs. Groups B and C). The Ca phosphate levels in Group A were significantly lower at 16 weeks (p < 0.05 vs. Groups B and C). There was a discrepancy in kinetics of AKP and BGP levels in Group A, such that the former showed a significant surge at 8 weeks (p < 0.05 vs. Groups B and C) followed by a decline at 16 weeks (p < 0.05 vs. Groups B and C), while the levels of the latter consistently decreased and became significantly decreased at 12 and 16 weeks (p < 0.05 vs. Groups B and C). In conclusion, these findings may lead to better understanding of the pathogenesis of osteoporosis in diabetic rats.
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Fine mapping of eight psoriasis susceptibility loci.
Eur. J. Hum. Genet.
PUBLISHED: 09-03-2014
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Previous studies have identified 41 independent genome-wide significant psoriasis susceptibility loci. After our first psoriasis genome-wide association study, we designed a custom genotyping array to fine-map eight genome-wide significant susceptibility loci known at that time (IL23R, IL13, IL12B, TNIP1, MHC, TNFAIP3, IL23A and RNF114) enabling genotyping of 2269 single-nucleotide polymorphisms (SNPs) in the eight loci for 2699 psoriasis cases and 2107 unaffected controls of European ancestry. We imputed these data using the latest 1000 Genome reference haplotypes, which included both indels and SNPs, to increase the marker density of the eight loci to 49?239 genetic variants. Using stepwise conditional association analysis, we identified nine independent signals distributed across six of the eight loci. In the major histocompatibility complex (MHC) region, we detected three independent signals at rs114255771 (P=2.94 × 10(-74)), rs6924962 (P=3.21 × 10(-19)) and rs892666 (P=1.11 × 10(-10)). Near IL12B we detected two independent signals at rs62377586 (P=7.42 × 10(-16)) and rs918518 (P=3.22 × 10(-11)). Only one signal was observed in each of the TNIP1 (rs17728338; P=4.15 × 10(-13)), IL13 (rs1295685; P=1.65 × 10(-7)), IL23A (rs61937678; P=1.82 × 10(-7)) and TNFAIP3 (rs642627; P=5.90 × 10(-7)) regions. We also imputed variants for eight HLA genes and found that SNP rs114255771 yielded a more significant association than any HLA allele or amino-acid residue. Further analysis revealed that the HLA-C*06-B*57 haplotype tagged by this SNP had a significantly higher odds ratio than other HLA-C*06-bearing haplotypes. The results demonstrate allelic heterogeneity at IL12B and identify a high-risk MHC class I haplotype, consistent with the existence of multiple psoriasis effectors in the MHC.European Journal of Human Genetics advance online publication, 3 September 2014; doi:10.1038/ejhg.2014.172.
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Long-term nitrogen fertilization of paddy soil shifts iron-reducing microbial community revealed by RNA-(13)C-acetate probing coupled with pyrosequencing.
ISME J
PUBLISHED: 08-29-2014
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Iron reduction is an important biogeochemical process in paddy soils, yet little is known about the microbial coupling between nitrogen and iron reduction. Here, we investigated the shift of acetate-metabolizing iron-reducers under long-term nitrogen fertilization using (13)C-acetate-based ribosomal RNA (rRNA)-stable isotope probing (SIP) and pyrosequencing in an incubation experiment, and the shift of putative iron-reducers in original field samples were investigated by 16S rRNA gene-based pyrosequencing. During SIP incubations, in the presence of iron(III) oxyhydroxides, more iron(II) formation and less methane production were detected in nitrogen-fertilized (N) compared with non-fertilized (NF) soil. In (13)C-rRNA from microcosms amended with ferrihydrite (FER), Geobacter spp. were the important active iron-reducers in both soils, and labeled to a greater extent in N (31% of the bacterial classified sequences) than NF soils (11%). Pyrosequencing of the total 16S rRNA transcripts from microcosms at the whole community level further revealed hitherto unknown metabolisms of potential FER reduction by microorganisms including Pseudomonas and Solibacillus spp. in N soil, Dechloromonas, Clostridium, Bacillus and Solibacillus spp. in NF soil. Goethite (GOE) amendment stimulated Geobacter spp. to a lesser extent in both soils compared with FER treatment. Pseudomonas spp. in the N soil and Clostridium spp. in the NF soil may also be involved in GOE reduction. Pyrosequencing results from field samples showed that Geobacter spp. were the most abundant putative iron-reducers in both soils, and significantly stimulated by long-term nitrogen fertilization. Overall, for the first time, we demonstrate that long-term nitrogen fertilization promotes iron(III) reduction and modulates iron-reducing bacterial community in paddy soils.The ISME Journal advance online publication, 29 August 2014; doi:10.1038/ismej.2014.159.
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Systematic discovery of cofactor motifs from ChIP-seq data by SIOMICS.
Methods
PUBLISHED: 08-27-2014
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Understanding transcriptional regulatory elements and particularly the transcription factor binding sites represents a significant challenge in computational biology. The chromatin immunoprecipitation followed by massive parallel sequencing (ChIP-seq) experiments provide an unprecedented opportunity to study transcription factor binding sites on the genome-wide scale. Here we describe a recently developed tool, SIOMICS, to systematically discover motifs and binding sites of transcription factors and their cofactors from ChIP-seq data. Unlike other tools, SIOMICS explores the co-binding properties of multiple transcription factors in short regions to predict motifs and binding sites. We have previously shown that the original SIOMICS method predicts motifs and binding sites of more cofactors in more accurate and time-effective ways than two popular methods. In this paper, we present the extended SIOMICS method, SIOMICS_Extension, and demonstrate its usage for systematic discovery of cofactor motifs and binding sites. The SIOMICS tool, including SIOMICS and SIOMICS_Extension, are available at http://hulab.ucf.edu/research/projects/SIOMICS/SIOMICS.html.
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[Effects of multiple-trough sampling design and algorithm on the estimation of population and individual pharmacokinetic parameters].
Yao Xue Xue Bao
PUBLISHED: 08-26-2014
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The purpose of this study is to investigate the effects of multiple-trough sampling design and nonlinear mixed effect modeling (NONMEM) algorithm on the estimation of population and individual pharmacokinetic parameters. Oxcarbazepine and tacrolimus were used as one-compartment and two-compartment model drugs, respectively. Seven sampling designs were investigated using various number of trough concentrations per individual ranging from 1-4. Monte Carlo simulations were performed to produce state-steady trough concentrations. One-compartment model was used to fit simulated data from oxcarbazepine and tacrolimus. The accuracy and precision of the estimated parameters were evaluated using the median prediction error (PE), the median absolute PE and boxplot. The results indicated that trough concentrations could yield reliable estimates of apparent clearance (CL/F). For oxcarbazepine, as the number of trough concentrations per subject increased, the accuracy and precision of CL/F, between-subject variability (BSV) of CL/F and residual variability (RUV) tended to be improved. For tacrolimus, however, although no improvement were observed in the accuracy of CL/F and BSV of CL/F, the PE distribution ranges were significantly narrowed and the RUV estimates were less bias and imprecise. In terms of algorithm, Monte Carlo importance sampling (IMP) and IMP assisted by mode a posteriori estimation (IMPMAP) were consistently better than other methods. Additionally, the sampling design had no significant effects on the individual parameter estimates, which were only depended on the interaction between BSV and RUV in various algorithms. Decreased in BSV and RUV levels can improve the accuracy and precision of the estimation for both population and individual pharmacokinetic parameter estimates.
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Magnetic solid phase extraction coupled with in situ derivatization for the highly sensitive determination of acidic phytohormones in rice leaves by UPLC-MS/MS.
Analyst
PUBLISHED: 08-23-2014
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A simple, rapid and sensitive method based on magnetic solid phase extraction (MSPE) coupled with in situ derivatization (ISD) was developed for the determination of endogenous acidic phytohormones in rice leaves by ultra-performance liquid chromatography-tandem mass spectrometry (UPLC-MS/MS) analysis. With this method, acidic phytohormones were extracted onto the surface of a TiO2/magnetic hollow mesoporous silica sphere (MHMSS) through hydrophilic interaction, and then in situ derivatization was performed by the subsequent addition of 3-bromoactonyltrimethylammonium bromide (BTA). Thus, the process integrated extraction, purification, and derivatization into one step. Additionally, the permanent positively charged moiety from BTA significantly improved the ionization efficiencies of the acidic phytohormones. Several parameters affecting the efficiencies of the extraction, derivatization, and desorption were evaluated. The signal intensities of acidic phytohormones increased by 2 to 481 fold after treatment with MSPE-ISD. Under the optimized conditions, several endogenous acidic phytohormones, including GA4, GA9, GA20, JA, IAA, and ABA, were identified and quantified in rice leaves by the MSPE-ISD method. The limits of detection (LODs) were in the range of 1.03-91.21 pg mL(-1). The relative recoveries ranged from 71.6-112.8%, with the intra- and interday relative standard deviations (RSDs) being less than 14.9% and 16.2%, respectively. Taken together, the proposed method provides a novel approach of combining magnetic solid phase extraction and in situ derivatization for the highly sensitive determination of endogenous acidic phytohormones.
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Tuneable complementary metamaterial structures based on graphene for single and multiple transparency windows.
Sci Rep
PUBLISHED: 08-22-2014
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Novel graphene-based tunable plasmonic metamaterials featuring single and multiple transparency windows are numerically studied in this paper. The designed structures consist of a graphene layer perforated with quadrupole slot structures and dolmen-like slot structures printed on a substrate. Specifically, the graphene-based quadrupole slot structure can realize a single transparency window, which is achieved without breaking the structure symmetry. Further investigations have shown that the single transparency window in the proposed quadrupole slot structure is more likely originated from the quantum effect of Autler-Townes splitting. Then, by introducing a dipole slot to the quadrupole slot structure to form the dolmen-like slot structure, an additional transmission dip could occur in the transmission spectrum, thus, a multiple-transparency-window system can be achieved (for the first time for graphene-based devices). More importantly, the transparency windows for both the quadrupole slot and the dolmen-like slot structures can be dynamically controlled over a broad frequency range by varying the Fermi energy levels of the graphene layer (through electrostatic gating). The proposed slot metamaterial structures with tunable single and multiple transparency windows could find potential applications in many areas such as multiple-wavelength slow-light devices, active plasmonic switching, and optical sensing.
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Draft Genome Sequence of Vibrio fortis Dalian14 Isolated from Diseased Sea Urchin (Strongylocentrotus intermedius).
Genome Announc
PUBLISHED: 07-05-2014
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Here, we report the draft genome sequence of Vibrio fortis Dalian14 isolated from diseased sea urchin (Strongylocentrotus intermedius) during disease outbreaks in North China. The availability of this genome sequence will facilitate the study of the mechanisms of pathogenicity and evolution of Vibrio species.
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The influence of decompressive craniectomy on the development of hydrocephalus: a review.
Arq Neuropsiquiatr
PUBLISHED: 06-18-2014
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Decompressive craniectomy (DC) is widely used to treat intracranial hypertension following traumatic brain injury (TBI) or cerebral vascular disease. Many studies have discussed complications of this procedure, and hydrocephalus is a common complication of DC. To further evaluate the relationship between DC and hydrocephalus, a review of the literature was performed. Numerous complications may arise after DC, including contusion or hematoma expansion, epilepsy, herniation of the cortex through a bone defect, CSF leakage through the scalp incision, infection, subdural effusion, hydrocephalus and "syndrome of the trephined". Several hydrocephalus predictors were identified; these included DC, distance from the midline, hygroma, age, injury severity, subarachnoid or intraventricular hemorrhage, delayed time to craniotomy, repeated operation, and duraplasity. However, results differed among studies. The impact of DC on hydrocephalus remains controversial.
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[Application value of three-dimensional female pelvic visualization modeling on transvaginal gynecological ultrasound imaging].
Zhonghua Fu Chan Ke Za Zhi
PUBLISHED: 04-18-2014
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To explore the application value of three-dimensional (3D) female pelvic visualization model on transvaginal gynecological ultrasound imaging.
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para-Quinodimethane-bridged perylene dimers and pericondensed quaterrylenes: the effect of the fusion mode on the ground states and physical properties.
Chemistry
PUBLISHED: 03-29-2014
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Polycyclic hydrocarbon compounds with a singlet biradical ground state show unique physical properties and promising material applications; therefore, it is important to understand the fundamental structure/biradical character/physical properties relationships. In this study, para-quinodimethane (p-QDM)-bridged quinoidal perylene dimers 4 and 5 with different fusion modes and their corresponding aromatic counterparts, the pericondensed quaterrylenes 6 and 7, were synthesized. Their ground-state electronic structures and physical properties were studied by using various experiments assisted with DFT calculations. The proaromatic p-QDM-bridged perylene monoimide dimer 4 has a singlet biradical ground state with a small singlet/triplet energy gap (-2.97?kcal?mol(-1)), whereas the antiaromatic s-indacene-bridged N-annulated perylene dimer 5 exists as a closed-shell quinoid with an obvious intramolecular charge-transfer character. Both of these dimers showed shorter singlet excited-state lifetimes, larger two-photon-absorption cross sections, and smaller energy gaps than the corresponding aromatic quaterrylene derivatives 6 and 7, respectively. Our studies revealed how the fusion mode and aromaticity affect the ground state and, consequently, the photophysical properties and electronic properties of a series of extended polycyclic hydrocarbon compounds.
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Effects of cholecystectomy on the changes of motility of Beagle dogs' sphincter of Oddi.
Acta Cir Bras
PUBLISHED: 03-18-2014
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To observe the effect of cholecystectomy on the changes of motion pattern of Beagle dogs' sphincter of Oddi (SO), and investigate the modulatory role of nitric oxide (NO) and cholecystokinin (CCK) in the regulation of SO.
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Personality traits and circadian blood pressure patterns: a 7-year prospective study.
Psychosom Med
PUBLISHED: 03-11-2014
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A nighttime dip in blood pressure is associated with decreased risk of cardiovascular morbidity and mortality. We examined whether personality traits predict nighttime dipping blood pressure.
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Tripterygium glycosides impairs the proliferation of granulosa cells and decreases the reproductive outcomes in female rats.
Birth Defects Res. B Dev. Reprod. Toxicol.
PUBLISHED: 02-11-2014
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This study was carried out to investigate the impact of tripterygium glycosides (TGs) on ovarian function of female rats in vitro and in vivo. In vitro studies showed that TG induced cells decrease at G1 phase and inhibited cell proliferation in rat granulosa cells. In vivo, female rats were intragastrically administered with TG at the dose of 60 mg/kg/day for consecutive 50 days. TG caused a prolonged estrous cycle, and a significant reduction in ovarian index, serum E2 level, and numbers of secondary and antral follicles (p < 0.05) in these rats. A significant reduction of viable embryos was demonstrated in TG-treated female rats after mating (p < 0.01). Further, we observed observed the reduced expression level of TGF-?1 after TG treatment in vitro and in vivo. Moreover, the expression of Smad2 and AKT was also decreased after TG treatment. These results suggest that TG can impair ovarian function through Smads-mediated TGF-?1 signal pathway.
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Resveratrol induces apoptosis of bladder cancer cells via miR?21 regulation of the Akt/Bcl?2 signaling pathway.
Mol Med Rep
PUBLISHED: 01-29-2014
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Resveratrol, an edible polyphenolic phytoalexin present in grapes and red wine, has been reported to inhibit proliferation and induce apoptosis of bladder cancer cells. In the present study, the molecular mechanisms of resveratrol on human bladder cancer cell apoptosis was examined. The effect of resveratrol on the viability and apoptosis of T24 and 5637 cells was measured using an MTT assay and flow cytometric analysis, respectively. Next, the effect of resveratrol on miR?21 expression was detected by real?time PCR. The expression of phospho?Akt and Bcl?2 following treatment with resveratrol or the downregulation of miR?21 expression were also measured. Resveratrol induced the cytotoxicity and apoptosis of T24 and 5637 cells in a dose?dependent manner. Resveratrol decreased the expression of miR?21, the level of phospho?Akt and Bcl?2 protein expression. In addition, the downregulation of miR?21 expression inhibited the level of phospho?Akt and Bcl?2 expression. Insulin?like growth factor?1 was able to reverse the effect of the miR?21 inhibitor on Bcl?2 expression and apoptosis in T24 and 5637 cells. Notably, overexpression of miR?21 expression was able to restore the inhibition of Akt activity, downregulation of Bcl?2 expression and apoptosis induced by resveratrol. Collectively, data revealed that the effect of resveratrol on bladder cancer cell apoptosis was due to miR?21 regulation of the Akt/Bcl?2 signaling pathway.
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Auxin transport and activity regulate stomatal patterning and development.
Nat Commun
PUBLISHED: 01-28-2014
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Stomata are two-celled valves that control epidermal pores whose spacing optimizes shoot-atmosphere gas exchange. They develop from protodermal cells after unequal divisions followed by an equal division and differentiation. The concentration of the hormone auxin, a master plant developmental regulator, is tightly controlled in time and space, but its role, if any, in stomatal formation is obscure. Here dynamic changes of auxin activity during stomatal development are monitored using auxin input (DII-VENUS) and output (DR5:VENUS) markers by time-lapse imaging. A decrease in auxin levels in the smaller daughter cell after unequal division presages the acquisition of a guard mother cell fate whose equal division produces the two guard cells. Thus, stomatal patterning requires auxin pathway control of stem cell compartment size, as well as auxin depletion that triggers a developmental switch from unequal to equal division.
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Transcriptome analysis of psoriasis in a large case-control sample: RNA-seq provides insights into disease mechanisms.
J. Invest. Dermatol.
PUBLISHED: 01-17-2014
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To increase our understanding of psoriasis, we used high-throughput complementary DNA sequencing (RNA-seq) to assay the transcriptomes of lesional psoriatic and normal skin. We sequenced polyadenylated RNA-derived complementary DNAs from 92 psoriatic and 82 normal punch biopsies, generating an average of ?38 million single-end 80-bp reads per sample. Comparison of 42 samples examined by both RNA-seq and microarray revealed marked differences in sensitivity, with transcripts identified only by RNA-seq having much lower expression than those also identified by microarray. RNA-seq identified many more differentially expressed transcripts enriched in immune system processes. Weighted gene coexpression network analysis (WGCNA) revealed multiple modules of coordinately expressed epidermal differentiation genes, overlapping significantly with genes regulated by the long noncoding RNA TINCR, its target gene, staufen-1 (STAU1), the p63 target gene ZNF750, and its target KLF4. Other coordinately expressed modules were enriched for lymphoid and/or myeloid signature transcripts and genes induced by IL-17 in keratinocytes. Dermally expressed genes were significantly downregulated in psoriatic biopsies, most likely because of expansion of the epidermal compartment. These results show the power of WGCNA to elucidate gene regulatory circuits in psoriasis, and emphasize the influence of tissue architecture in both differential expression and coexpression analysis.
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Facile synthesis of magnetic molecularly imprinted polymers and its application in magnetic solid phase extraction for fluoroquinolones in milk samples.
J Chromatogr A
PUBLISHED: 01-02-2014
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In this work, we proposed a simple co-mixing method to fabricate magnetic molecularly imprinted polymers (magnetic MIPs). MIPs were commercial products while magnetic nanoparticles (MNPs) were prepared by chemical oxidation and solvothermal methods. When MNPs and MIPs (with mass ratio 1:1) were co-mixed and vortexed evenly in methanol, they could assemble into magnetic composites spontaneously and thus be magnetically separable. To testify the feasibility of the magnetic composites in sample preparation, the resultant magnetic MIPs were applied as sorbents for magnetic solid-phase extraction (MSPE) of fluoroquinolones (FQs) in milk samples. Under optimized conditions, a rapid, convenient, and efficient method for the determination of three FQs in milk samples was established by magnetic MIPs based MSPE coupling with high performance liquid chromatography with ultraviolet detector (HPLC-UV). The limits of detection (LODs) for three FQs were found to be 1.8-3.2ng/g. The intra- and inter-day relative standard deviations (RSDs) were less than 9.5% and 12.5%, respectively. The recoveries of FQs for two spiked milk samples were in the range from 94.0% to 124.4% with the RSDs less than 11.6%.
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[Molluscicidal effect of plastic film mulch covering method].
Zhongguo Xue Xi Chong Bing Fang Zhi Za Zhi
PUBLISHED: 12-24-2013
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To evaluate the molluscicidal effect of the plastic film mulch covering method.
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SIOMICS: a novel approach for systematic identification of motifs in ChIP-seq data.
Nucleic Acids Res.
PUBLISHED: 12-09-2013
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The identification of transcription factor binding motifs is important for the study of gene transcriptional regulation. The chromatin immunoprecipitation (ChIP), followed by massive parallel sequencing (ChIP-seq) experiments, provides an unprecedented opportunity to discover binding motifs. Computational methods have been developed to identify motifs from ChIP-seq data, while at the same time encountering several problems. For example, existing methods are often not scalable to the large number of sequences obtained from ChIP-seq peak regions. Some methods heavily rely on well-annotated motifs even though the number of known motifs is limited. To simplify the problem, de novo motif discovery methods often neglect underrepresented motifs in ChIP-seq peak regions. To address these issues, we developed a novel approach called SIOMICS to de novo discover motifs from ChIP-seq data. Tested on 13 ChIP-seq data sets, SIOMICS identified motifs of many known and new cofactors. Tested on 13 simulated random data sets, SIOMICS discovered no motif in any data set. Compared with two recently developed methods for motif discovery, SIOMICS shows advantages in terms of speed, the number of known cofactor motifs predicted in experimental data sets and the number of false motifs predicted in random data sets. The SIOMICS software is freely available at http://eecs.ucf.edu/?xiaoman/SIOMICS/SIOMICS.html.
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Dibenzoheptazethrene Isomers with Different Biradical Characters: An Exercise of Clars Aromatic Sextet Rule in Singlet Biradicaloids.
J. Am. Chem. Soc.
PUBLISHED: 11-20-2013
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Clars aromatic sextet rule has been widely used for the prediction of the reactivity and stability of polycyclic aromatic hydrocarbons with a closed-shell electronic configuration. Recent advances in open-shell biradicaloids have shown that the number of aromatic sextet rings plays an important role in determination of their ground states. In order to test the validity of this rule in singlet biradicaloids, the two soluble and stable dibenzoheptazethrene isomers DBHZ1 and DBHZ2 were prepared by different synthetic approaches and isolated in crystalline form. These two molecules have different numbers of aromatic sextet rings in their respective biradical resonance forms and thus are expected to exhibit varied singlet biradical character. This assumption was verified by different experimental methods, including nuclear magnetic resonance (NMR), electron spin resonance (ESR), superconducting quantum interference device (SQUID), steady-state and transient absorption spectroscopy (TA), and X-ray crystallographic analysis, assisted by unrestricted symmetry-broken density functional theory (DFT) calculations. DBHZ2, with more aromatic sextet rings in the biradical form, was demonstrated to possess greater biradical character than DBHZ1; as a result, DBHZ2 exhibited an intense one-photon absorption (OPA) in the near-infrared region (?abs(max) = 804 nm) and a large two-photon absorption (TPA) cross-section (?((2))max = 2800 GM at 1600 nm). This investigation together with previous studies indicates that Clars aromatic sextet rule can be further extended to the singlet biradicaloids to predict their ground states and singlet biradical characters.
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Manipulating the surface coating of ultra-small Gd2O3 nanoparticles for improved T1-weighted MR imaging.
Biomaterials
PUBLISHED: 10-18-2013
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In this report, monodispersed ultra-small Gd2O3 nanoparticles capped with hydrophobic oleic acid (OA) were synthesized with average particle size of 2.9 nm. Two methods were introduced to modify the surface coating to hydrophilic for bio-applications. With a hydrophilic coating, the polyvinyl pyrrolidone (PVP) coated Gd2O3 nanoparticles (Gd2O3-PVP) showed a reduced longitudinal T1 relaxation time compared with OA and cetyltrimethylammonium bromide (CTAB) co-coated Gd2O3 (Gd2O3-OA-CTAB) in the relaxation study. The Gd2O3-PVP was thus chosen for its further application study in MRI with an improved longitudinal relaxivity r1 of 12.1 mm(-)(1) s(-1) at 7 T, which is around 3 times as that of commercial contrast agent Magnevist(®). In vitro cell viability in HK-2 cell indicated negligible cytotoxicity of Gd2O3-PVP within preclinical dosage. In vivo MR imaging study of Gd2O3-PVP nanoparticles demonstrated considerable signal enhancement in the liver and kidney with a long blood circulation time. Notably, the OA capping agent was replaced by PVP through ligand exchange on the Gd2O3 nanoparticle surface. The hydrophilic PVP grants the Gd2O3 nanoparticles with a polar surface for bio-application, and the obtained Gd2O3-PVP could be used as an in vivo indicator of reticuloendothelial activity.
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[Analysis of clinical features and early warning indicators of death from hand, foot and mouth disease in Shandong province].
Zhonghua Yu Fang Yi Xue Za Zhi
PUBLISHED: 08-10-2013
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To understand the clinical features of death from hand, foot and mouth disease (HFMD) and to explore the early warning index of HFMD death.
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Nanomagnetism study of highly-ordered iron oxide nanocrystal assemblies fabricated by the Langmuir-Blodgett technique.
Phys Chem Chem Phys
PUBLISHED: 08-01-2013
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Iron oxide nanocrystals are ideal building blocks for the construction of flexible nanodevices whose performance can be modulated by controlling the morphology of isolated particles and their organizational form. This work demonstrates the fabrication of high quality Langmuir-Blodgett (LB) nanocrystal assemblies with limited overlapping and higher coverage by systemically and combinatorially optimizing the parameters of compression pressure and quantity of spread nanocrystals. Monodispersed iron oxide nanocrystals with a diameter of 11.8 nm were synthesized by thermal decomposition of Fe(CO)5 in trioctylamine with the presence of oleic acid. Multilayer nanocrystal assemblies were obtained through a layer-by-layer (LBL) process by repeating the transfer procedure after their hydrophilicity had been improved via treatment in a UV-ozone oven. The quality of nanocrystal assemblies was investigated by UV-vis spectrometry and scanning electron microscopy. The nanomagnetism for the nanostructures of different combination manners was studied systemically by a superconducting quantum interference device (SQUID). A lower superparamagnetic blocking temperature was found in the monolayer Fe3O4 nanocrystal assembly. The superparamagnetic blocking temperature in magnetic nanocrystal assemblies could be tuned through modifying the interparticle interactions among the interlayer and intralayers by controlling the layer number of the assemblies.
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[Causes of re-emergence of Oncomelania snails in hardened ditches].
Zhongguo Xue Xi Chong Bing Fang Zhi Za Zhi
PUBLISHED: 07-31-2013
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To understand the impact factors of the re-emergence of Oncomelania snails in hardened ditches so as to find out the measures to improve the effect of snail eradication.
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Experimental investigation of the penetration of ultrasound nanobubbles in a gastric cancer xenograft.
Nanotechnology
PUBLISHED: 07-23-2013
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Nanobubbles as a type of ultrasound contrast agent have attracted much interest in recent years due to their many advantages, such as strong penetrating power and high stability. However, there is still insufficient morphological evidence concerning gas-filled nanobubbles in tumor tissue spaces and tumor angiogenesis. We used a gastric cancer xenograft as an example to study this question. Nanobubbles with a particle size of 435.2 ± 60.53 nm were prepared and compared with SonoVue® microbubbles in vitro and in vivo, and they exhibited a superior contrast imaging effect. After excluding the impact of the nanobubbles in blood vessels through saline flush, we used an ultrasound burst and frozen sectioning to investigate the distribution of nanobubbles in the gastric cancer xenografts and confirmed this by transmission electron microscopy. Preliminary results showed that the nanobubbles were able to pass through the gaps between the endothelial cells in the tumor vascular system to enter the tissue space. These findings could provide morphological evidence for extravascular ultrasound imaging of tumors and serve as a foundation for the application of nanobubbles in extravascular tumor-targeted ultrasonic diagnostics and therapy.
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[Association between MAOA-u VNTR polymorphism and its interaction with stressful life events and major depressive disorder in adolescents].
Zhongguo Dang Dai Er Ke Za Zhi
PUBLISHED: 07-20-2013
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To investigate whether the genetic polymorphism, upstream variable number of tandem repeats (uVNTR), in the monoamine oxidase A (MAOA) gene, is associated with major depressive disorder (MDD) in adolescents and to test whether there is gene-environment interaction between MAOA-uVNTR polymorphism and stressful life events (SLEs).
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Prediction of protein methylation sites using conditional random field.
Protein Pept. Lett.
PUBLISHED: 06-19-2013
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Protein methylation is an important and reversible post-translational modification which regulates diverse protein properties. Many methylation sites on arginine and lysine have been identification through experiments. However, experimental identification without prior knowledge is laborious and costly. Hence, there is interest in the development of computational methods for reliable prediction of methylation sites. Prediction of methylation sites may provide researches with useful information for further productivity in methylation candidate sites discovery. This work proposes Methcrf, a computational predictor based on conditional random field (CRF) for predicting protein methylation sites limit to lysine and arginine residues due to the absence of enough experimentally verified data for other residues. The approach is developed to consider combining protein sequence features with structural information such as solvent accessibility of amino acids that surround the methylation sites. In 10-fold cross validation Methcrf can achieve the area under receiver operating characteristic curve (AUC) of 0.85 and 0.80 for arginine and lysine, respectively. The proposed method has comparable performance with previous methods for accurately predicting methylation sites.
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Genetic variants of Orientia tsutsugamushi in domestic rodents, northern China.
Emerging Infect. Dis.
PUBLISHED: 06-15-2013
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We screened Orientia tsutsugamushi from 385 domestic rodents and 19 humans with scrub typhus in rural Taian District, Shandong Province, a new scrub typhus epidemic area in northern China. Sequence analysis identified 7 genotypes in the rodents, of which 2 were also identified in the humans.
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MicroRNA miR-302 inhibits the tumorigenicity of endometrial cancer cells by suppression of Cyclin D1 and CDK1.
Cancer Lett.
PUBLISHED: 06-04-2013
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MicroRNA miR-302 has been found to induce some tumor cell lines to "transdifferentiate" into miRNA-induced pluripotent stem cells (mirPS), thereby inhibiting tumor cell proliferation and reducing tumorigenicity. This study firstly found that miR-302 inhibited the proliferation and migration of endometrial cell line, Ishikawa and HEC-1-B, and arrested cell cycle at the G2/M phase. In addition, miR-302 inhibited tumorigenicity in immunodeficient mice transplanted with Ishikawa cells. Microarray and Western blotting results showed that miR-302 significantly inhibited CDK1 and Cyclin D1 gene expression in Ishikawa cells. MiR-302 directly targeted Cyclin D1, but indirectly regulated CDK1 gene expression.
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Acetic acid inhibits nutrient uptake in Saccharomyces cerevisiae: auxotrophy confounds the use of yeast deletion libraries for strain improvement.
Appl. Microbiol. Biotechnol.
PUBLISHED: 04-21-2013
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Acetic acid inhibition of yeast fermentation has a negative impact in several industrial processes. As an initial step in the construction of a Saccharomyces cerevisiae strain with increased tolerance for acetic acid, mutations conferring resistance were identified by screening a library of deletion mutants in a multiply auxotrophic genetic background. Of the 23 identified mutations, 11 were then introduced into a prototrophic laboratory strain for further evaluation. Because none of the 11 mutations was found to increase resistance in the prototrophic strain, potential interference by the auxotrophic mutations themselves was investigated. Mutants carrying single auxotrophic mutations were constructed and found to be more sensitive to growth inhibition by acetic acid than an otherwise isogenic prototrophic strain. At a concentration of 80 mM acetic acid at pH 4.8, the initial uptake of uracil, leucine, lysine, histidine, tryptophan, phosphate, and glucose was lower in the prototrophic strain than in a non-acetic acid-treated control. These findings are consistent with two mechanisms by which nutrient uptake may be inhibited. Intracellular adenosine triphosphate (ATP) levels were severely decreased upon acetic acid treatment, which likely slowed ATP-dependent proton symport, the major form of transport in yeast for nutrients other than glucose. In addition, the expression of genes encoding some nutrient transporters was repressed by acetic acid, including HXT1 and HXT3 that encode glucose transporters that operate by facilitated diffusion. These results illustrate how commonly used genetic markers in yeast deletion libraries complicate the effort to isolate strains with increased acetic acid resistance.
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Pushing extended p-quinodimethanes to the limit: stable tetracyano-oligo(N-annulated perylene)quinodimethanes with tunable ground states.
J. Am. Chem. Soc.
PUBLISHED: 04-16-2013
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p-Quinodimethane (p-QDM) is a fundamental building block for the design of ?-conjugated systems with low band gap and open-shell biradical character. However, synthesis of extended p-QDMs has usually suffered from their intrinsic high reactivity and poor solubility. In this work, benzannulation together with terminal cyano-substitution was demonstrated to be an efficient approach for the synthesis of a series of soluble and stable tetracyano-oligo(N-annulated perylene)quinodimethanes nPer-CN (n = 1-6), with the longest molecule having 12 para-linked benzenoid rings! The geometry and electronic structures of these oligomers were investigated by steady-state and transient absorption spectroscopy, nuclear magnetic resonance, electron spin resonance, superconducting quantum interference device, and FT Raman spectroscopy assisted by density functional theory calculations. They showed tunable ground states, varying from a closed-shell quinoidal structure for monomer, to a singlet biradical for dimer, trimer, and tetramer, and to a triplet biradical for pentamer and hexamer. Large two-photon absorption cross-section values were observed in the near-infrared range, which also exhibited a clear chain-length dependence.
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Withdrawal of GnRH agonist decreases oestradiol and VEGF concentrations in high responders.
Reprod. Biomed. Online
PUBLISHED: 04-10-2013
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This study evaluated whether the withdrawal of a gonadotrophin-releasing hormone (GnRH) agonist before triggering ovulation reduces the incidence of ovarian hyperstimulation syndrome (OHSS) in high-risk infertility patients who were treated with gonadotrophins. GnRH agonist was withdrawn for 2 or 3 days when dominant follicles were ?14mm in diameter, according to the GnRH agonist long protocol. Non-withdrawal of GnRH agonist was used as control. The serum concentration of oestradiol on the ovulation trigger day was significantly decreased in the GnRH agonist withdrawal group compared with the control group (5750.78±2344.77pg/ml versus 8076.43±1981.67pg/ml); however, the number of retrieved oocytes and the fertilization rate were similar between the groups. In addition, the concentrations of vascular endothelial growth factor in plasma on day of human chorionic gonadotrophin administration and follicular fluid on the oocyte retrieval day were decreased following GnRH agonist withdrawal. In fresh embryo transfer cycles, rates of clinical pregnancy, implantation and OHSS were not different between the groups. When GnRH agonist withdrawal was followed by total embryos cryopreserved, the rate of OHSS was decreased compared with the control group (0% versus 8.70%). Clinical pregnancy rates in cryopreserved embryo transfer cycles were comparable between the two groups.
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Controllable synthesis of ZnO nanoparticles with high intensity visible photoemission and investigation of its mechanism.
Nanotechnology
PUBLISHED: 04-09-2013
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ZnO is known as a good photoluminescent semiconductor due to its ability to emit visible light. However, the visible emission mechanism is still under debate. In this work, we have successfully synthesized nanoparticles using LiOH, KOH and NaOH as bases and have achieved visible emission of various colours, such as blue, cyan, green and orange. We demonstrate that LiOH is the most efficient base to control the properties of ZnO nanoparticle emission by varying LiOH concentration. Moreover, detailed studies by TEM, UV and XRD show that ZnO particle size plays an important role in the colour of the emitted light and smaller particles tend to emit shorter wavelength photons. The visible emission is suggested to arise from an electron transition from the conduction band to a deep-trapped defect state. Our experimental results suggest the presence of oxygen vacancies on the ZnO nanoparticle surface.
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Dose-Dependent Protective Effect of Bisperoxovanadium against Acute Cerebral Ischemia in a Rat Model of Ischemia/Reperfusion Injury.
Int J Mol Sci
PUBLISHED: 04-07-2013
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PTEN (phosphatase and tensin homologue deleted on chromosome 10) is a dual-specificity lipid and protein phosphatase. The loss of PTEN was originally discovered in numerous human cancers. PTEN inhibition by bisperoxovanadium (bpV) reduces neurological damage after ischemic brain injury. The purpose of this study was to identify the optimal neuroprotective dose of bpV when administrated after focal ischemia/reperfusion (I/R) injury in rats. Focal I/R injury was induced using the middle cerebral artery occlusion method. bpV at doses of 0.25, 0.50 and 1.0 mg/kg were injected intraperitoneally just after reperfusion, with saline serving as a vehicle control. A maximal reduction in brain injury was observed with 1.0 mg/kg bpV. This dose of bpV also significantly blocked apoptosis in the penumbral cortex of rats. This beneficial effect was associated with the increasing levels of Akt phosphorylation in the penumbral cortex. These results demonstrate that the pharmacological inhibition of PTEN protects against I/R injury in a dose-dependent manner and the protective effect might be induced through upregulation of the phosphoinositide-3 kinase/Akt pro-survival pathway, suggesting a new therapeutic strategy to combat ischemic brain injury.
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Constitutively active Foxo3 in oocytes preserves ovarian reserve in mice.
Nat Commun
PUBLISHED: 04-04-2013
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During female reproductive life, ovarian follicle reserve is reduced by maturation and atresia until menopause ensues. Foxo3 is required to maintain the ovarian reserve in mice. Here we show that overexpression of constitutively active FOXO3 can increase ovarian reproductive capacity in mice. We find increased follicle numbers and decreased gonadotropin levels in aging FOXO3-transgenic mice compared with wild-type littermates, suggesting maintenance of a greater ovarian reserve. Based on cumulative progeny in aging animals, we find 31-49% increased fertility in transgenic females. The gene expression profile of Foxo3-/- knockout ovaries appears older than that of wild-type littermates, and the transgene induces a younger-looking profile, restoring much of the wild-type transcriptome. This is the first gain-of-function model of augmented reproductive reserve in mice, thus emphasizing the role of Foxo3 as a guardian of the ovarian follicle pool in mammals and a potential determinant of the onset of menopause.
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FSH modulates the expression of inhibin-alpha and the secretion of inhibins via orphan nuclear receptor NUR77 in ovarian granulosa cells.
Mol. Reprod. Dev.
PUBLISHED: 03-06-2013
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It has been previously reported that follicle-stimulating hormone (FSH) regulates the expression of inhibin-alpha in human granulosa cells, but the precise molecular pathway remains unknown. In the present study, we investigated the role of the orphan nuclear receptor, NUR77, in both the transcriptional regulation of the inhibin ?-subunit gene and the secretion of inhibins. Our results showed that in a human granulosa cell tumor-derived cell line (KGN) and in human granulosa-lutein cells (hGL), FSH induced the expression of NUR77 and inhibin-alpha, although inhibin-alpha expression did not increased following FSH treatment if NUR77 was knocked down. Furthermore, simply overexpressing or reducing NUR77 levels affected inhibin-alpha expression, while NUR77 overexpression improved the secretion of inhibin A and B from human granulosa cells. In addition, chromatin immunoprecipitation-PCR, avidin-biotin-conjugated DNA precipitation, and luciferase reporter assays confirmed that NUR77 directly regulated the transcription of the inhibin-alpha gene through the specific NGFI-B response element located within its promoter. In the ovarian granulosa cells of the Nur77 knockout mice, the mRNA levels of inhibin-alpha were decreased relative to wild-type mice. These data indicate a role of NUR77 in the regulation of inhibin-alpha in ovarian granulosa cells.
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Effects of CYP3A4 and CYP3A5 polymorphisms on tacrolimus pharmacokinetics in Chinese adult renal transplant recipients: a population pharmacokinetic analysis.
Pharmacogenet. Genomics
PUBLISHED: 03-06-2013
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Tacrolimus is used clinically for the long-term treatment of antirejection of transplanted organs in liver and kidney transplant recipients, although dose optimization is poorly managed. The aim of this study was to examine the association between tacrolimus pharmacokinetic variability and CYP3A4 and CYP3A5 genotypes by a population pharmacokinetic analysis based on routine drug monitoring data in adult renal transplant recipients.
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Fano resonance and step-like transmission via guide-mode resonance structure.
Opt Lett
PUBLISHED: 03-05-2013
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A two-layer guide-mode resonance structure made of shallow gratings deposited on the Kerr active guiding layer is used to realize high-quality Fano resonance and step-like transmission. The step-like transmission is designed to work between the perfect transmission peak and the dip of the asymmetrical Fano spectrum. It is demonstrated that the steep transition in the transmission should be attributed to the strong field localization in cases of both high and low transmission states.
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Depressive disorders among children in the transforming China: an epidemiological survey of prevalence, correlates, and service use.
Depress Anxiety
PUBLISHED: 02-27-2013
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To date, no one-phase survey of childhood depression has been performed in China that involves both urban and rural community children. The objective of this study was to determine the prevalence, correlates, and mental health service utilization of depressive disorders (DDs) in a community-based sample of 6-14-year-old children in south-central China.
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Determination of endogenous brassinosteroids in plant tissues using solid-phase extraction with double layered cartridge followed by high-performance liquid chromatography-tandem mass spectrometry.
Phytochem Anal
PUBLISHED: 02-25-2013
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Brassinosteroids (BRs) are a group of important phytohormones that play vital roles in plant growth, development and a series of physiological phenomena. In order to understand biosynthesis, degradation and metabolic pathways of BRs, a reliable analytical method of BRs with effective sample pre-treatment process is favourable.
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ChIPModule: systematic discovery of transcription factors and their cofactors from ChIP-seq data.
Pac Symp Biocomput
PUBLISHED: 02-21-2013
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We have developed a novel approach called ChIPModule to systematically discover transcription factors and their cofactors from ChIP-seq data. Given a ChIP-seq dataset and the binding patterns of a large number of transcription factors, ChIPModule can efficiently identify groups of transcription factors, whose binding sites significantly co-occur in the ChIP-seq peak regions. By testing ChIPModule on simulated data and experimental data, we have shown that ChIPModule identifies known cofactors of transcription factors, and predicts new cofactors that are supported by literature. ChIPModule provides a useful tool for studying gene transcriptional regulation.
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The peroxisomal enzyme L-PBE is required to prevent the dietary toxicity of medium-chain fatty acids.
Cell Rep
PUBLISHED: 02-19-2013
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Specific metabolic pathways are activated by different nutrients to adapt the organism to available resources. Although essential, these mechanisms are incompletely defined. Here, we report that medium-chain fatty acids contained in coconut oil, a major source of dietary fat, induce the liver ?-oxidation genes Cyp4a10 and Cyp4a14 to increase the production of dicarboxylic fatty acids. Furthermore, these activate all ?- and ?-oxidation pathways through peroxisome proliferator activated receptor (PPAR) ? and PPAR?, an activation loop normally kept under control by dicarboxylic fatty acid degradation by the peroxisomal enzyme L-PBE. Indeed, L-pbe(-/-) mice fed coconut oil overaccumulate dicarboxylic fatty acids, which activate all fatty acid oxidation pathways and lead to liver inflammation, fibrosis, and death. Thus, the correct homeostasis of dicarboxylic fatty acids is a means to regulate the efficient utilization of ingested medium-chain fatty acids, and its deregulation exemplifies the intricate relationship between impaired metabolism and inflammation.
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Influence of glibenclamide on outcome in patients with type 2 diabetes and traumatic brain injury.
Clin Neurol Neurosurg
PUBLISHED: 02-03-2013
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The influence of sulfonylurea receptor 1 (SUR1) and its inhibitor glibenclamide on progressive secondary hemorrhage (PSH), progressive hemorrhagic necrosis (PHN), and brain edema has been studied in rat models of traumatic brain injury (TBI) and ischemia. These studies indicate that blocking SUR1 may exert protective effects in terms of outcome.
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Susceptibility-associated genetic variation at IL12B enhances Th1 polarization in psoriasis.
Hum. Mol. Genet.
PUBLISHED: 01-31-2013
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The IL12B gene encodes the common p40 subunit of IL-12 and IL-23, cytokines with key roles in Th1 and Th17 biology, respectively, and genetic variation in this region significantly influences risk of psoriasis. Here, we demonstrate that a psoriasis-associated risk haplotype at the IL12B locus leads to increased expression of IL12B by monocytes and correlated with increased serum levels of IL-12, IFN-? and the IFN-? induced chemokine, CXCL10. In contrast, serum IL-23 levels were decreased in risk carriers when compared with non-carriers. We further demonstrate that IL-12 is increased in psoriatic skin and that risk carriers manifest a skewing of the inflammatory network toward stronger IFN-? responses. Taken together, our data demonstrate that the risk variant in IL12B associates with its increased expression and predisposes to stronger Th1 polarization through deviation of the local inflammatory environment toward increased IL-12/IFN-? at the expense of IL-23/IL-17 responses.
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Clinical and epidemiological study on severe fever with thrombocytopenia syndrome in Yiyuan County, Shandong Province, China.
Am. J. Trop. Med. Hyg.
PUBLISHED: 01-21-2013
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Severe fever with thrombocytopenia syndrome (SFTS) is an emerging infectious disease in China. Polymerase chain reaction and enzyme-linked immunosorbent assay were used to detect SFTS virus (SFTSV) and Anaplasma phagocytophilum in previous clinically diagnosed human anaplasmosis patients and SFTS patients. A serosurvey for SFTSV infection was also conducted on healthy persons and animals in Yiyuan County in Shandong Province of China. Among 21 patients SFTSV was detected in 17 (81%) however A. phagocytophilum was not detected in any of the patients. The seroprevalence rate of IgG antibody to SFTSV antigens was 1.3% (1 of 78) in healthy persons, 95% (19 of 20) in goats, 50% (1 of 2) in dogs, 0% in cattle (0 of 21), and rats (Rattus norvegicus) (0 of 35). The conclusion of this study was that co-infection of SFTSV and A. phagocytophilum are rare in SFTS patients and goats might play an important role in transmission of SFTSV.
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Direct observation of lithium-ion transport under an electrical field in LixCoO2 nanograins.
Sci Rep
PUBLISHED: 01-17-2013
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The past decades have witnessed the development of many technologies based on nanoionics, especially lithium-ion batteries (LIBs). Now there is an urgent need for developing LIBs with good high-rate capability and high power. LIBs with nanostructured electrodes show great potentials for achieving such goals. However, the nature of Li-ion transport behaviors within the nanostructured electrodes is not well clarified yet. Here, Li-ion transport behaviors in Li(x)CoO(2) nanograins are investigated by employing conductive atomic force microscopy (C-AFM) technique to study the local Li-ion diffusion induced conductance change behaviors with a spatial resolution of ~10 nm. It is found that grain boundary has a low Li-ion diffusion energy barrier and provides a fast Li-ion diffusion pathway, which is also confirmed by our first principles calculation. This information provides important guidelines for designing high performance LIBs from a point view of optimizing the electrode material microstructures and the development of nanoionics.
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Computational study of the blood flow in three types of 3D hollow fiber membrane bundles.
J Biomech Eng
PUBLISHED: 01-11-2013
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The goal of this study is to develop a computational fluid dynamics (CFD) modeling approach to better estimate the blood flow dynamics in the bundles of the hollow fiber membrane based medical devices (i.e., blood oxygenators, artificial lungs, and hemodialyzers). Three representative types of arrays, square, diagonal, and random with the porosity value of 0.55, were studied. In addition, a 3D array with the same porosity was studied. The flow fields between the individual fibers in these arrays at selected Reynolds numbers (Re) were simulated with CFD modeling. Hemolysis is not significant in the fiber bundles but the platelet activation may be essential. For each type of array, the average wall shear stress is linearly proportional to the Re. For the same Re but different arrays, the average wall shear stress also exhibits a linear dependency on the pressure difference across arrays, while Darcys law prescribes a power-law relationship, therefore, underestimating the shear stress level. For the same Re, the average wall shear stress of the diagonal array is approximately 3.1, 1.8, and 2.0 times larger than that of the square, random, and 3D arrays, respectively. A coefficient C is suggested to correlate the CFD predicted data with the analytical solution, and C is 1.16, 1.51, and 2.05 for the square, random, and diagonal arrays in this paper, respectively. It is worth noting that C is strongly dependent on the array geometrical properties, whereas it is weakly dependent on the flow field. Additionally, the 3D fiber bundle simulation results show that the three-dimensional effect is not negligible. Specifically, velocity and shear stress distribution can vary significantly along the fiber axial direction.
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Preparation of protamine cationic nanobubbles and experimental study of their physical properties and in vivo contrast enhancement.
Ultrasound Med Biol
PUBLISHED: 01-11-2013
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In this study, we aimed to prepare a novel type of microbubble (MB), protamine cationic nanobubble (NB), to provide a new vector for tumor gene therapy. We prepared cationic NBs with protamine and other lipid components using mechanical oscillation. The protamine cationic NBs had a mean diameter of 521.2 ± 37.57 nm, a zeta potential of +18.5 mV, and a gene-carrying capacity of 15.69 ?g androgen receptor (AR) siRNA per 10(8) NBs. The cationic NBs exhibited superior contrast enhancement for in vivo imaging compared with SonoVue (Bracco, Geneva, Switzerland), and their physical properties did not change significantly after 1 wk; meanwhile, the transfection efficiency of the cationic NBs in androgen-independent prostate cancer cells mediated by ultrasound irradiation was better than that of liposomes (82.17 ± 7.4% vs. 55.04 ± 5.4%, p < 0.01). Therefore, the protamine cationic NB can be considered for use as a novel type of gene-loading MB for ultrasound imaging and MB-mediated gene therapy of tumors.
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Construction and in vitro/in vivo targeting of PSMA-targeted nanoscale microbubbles in prostate cancer.
Prostate
PUBLISHED: 01-03-2013
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Prostate-specific membrane antigen (PSMA) is a highly specific biological marker and treatment target for prostate cancer. So ultrasound molecular imaging using PSMA antibody-loaded targeted nanoscale microbubbles (MBs) may contribute to the early diagnosis of prostate cancer.
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iSNO-PseAAC: predict cysteine S-nitrosylation sites in proteins by incorporating position specific amino acid propensity into pseudo amino acid composition.
PLoS ONE
PUBLISHED: 01-02-2013
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Posttranslational modifications (PTMs) of proteins are responsible for sensing and transducing signals to regulate various cellular functions and signaling events. S-nitrosylation (SNO) is one of the most important and universal PTMs. With the avalanche of protein sequences generated in the post-genomic age, it is highly desired to develop computational methods for timely identifying the exact SNO sites in proteins because this kind of information is very useful for both basic research and drug development. Here, a new predictor, called iSNO-PseAAC, was developed for identifying the SNO sites in proteins by incorporating the position-specific amino acid propensity (PSAAP) into the general form of pseudo amino acid composition (PseAAC). The predictor was implemented using the conditional random field (CRF) algorithm. As a demonstration, a benchmark dataset was constructed that contains 731 SNO sites and 810 non-SNO sites. To reduce the homology bias, none of these sites were derived from the proteins that had [Formula: see text] pairwise sequence identity to any other. It was observed that the overall cross-validation success rate achieved by iSNO-PseAAC in identifying nitrosylated proteins on an independent dataset was over 90%, indicating that the new predictor is quite promising. Furthermore, a user-friendly web-server for iSNO-PseAAC was established at http://app.aporc.org/iSNO-PseAAC/, by which users can easily obtain the desired results without the need to follow the mathematical equations involved during the process of developing the prediction method. It is anticipated that iSNO-PseAAC may become a useful high throughput tool for identifying the SNO sites, or at the very least play a complementary role to the existing methods in this area.
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Inhibition of phosphatase and tensin homolog deleted on chromosome 10 decreases rat cortical neuron injury and blood-brain barrier permeability, and improves neurological functional recovery in traumatic brain injury model.
PLoS ONE
PUBLISHED: 01-01-2013
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Recent evidence has supported the neuroprotective effect of bpV (pic), an inhibitor of phosphatase and tensin homolog deleted on chromosome 10 (PTEN), in models of ischemic stroke. However, whether PTEN inhibitors improve long-term functional recovery after traumatic brain injury (TBI) and whether PTEN affects blood brain barrier (BBB) permeability need further elucidation. The present study was performed to address these issues.
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Impact of thoracic injury on traumatic brain injury outcome.
PLoS ONE
PUBLISHED: 01-01-2013
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To assessed the significance of thoracic injury on the 30-day mortality and outcome of traumatic brain injury (TBI).
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Psychiatric illness and intellectual disability in the Prader-Willi syndrome with different molecular defects--a meta analysis.
PLoS ONE
PUBLISHED: 01-01-2013
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Several studies have suggested a difference in clinical features of intellectual ability and psychiatric illness in the Prader-Willi syndrome (PWS) with the 15q11-q13 paternal deletion and maternal uniparental disomy (mUPD). Our objective was to appraise evidence on this association through a meta-analysis.
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Pancreaticoduodenectomy combined with vascular resection and reconstruction for patients with locally advanced pancreatic cancer: a multicenter, retrospective analysis.
PLoS ONE
PUBLISHED: 01-01-2013
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The aim of this study was to present the therapeutic outcome of patients with locally advanced pancreatic cancer treated with pancreatoduodenectomy combined with vascular resection and reconstruction in addition to highlighting the mortality/morbidity and main prognostic factors associated with this treatment.
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A selective pretreatment method for determination of endogenous active brassinosteroids in plant tissues: double layered solid phase extraction combined with boronate affinity polymer monolith microextraction.
Plant Methods
PUBLISHED: 01-01-2013
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BACKGROUND: Brassinosteriods (BRs), a group of important phytohormones, have various effects on plant growth and development. However, their physiological functions in plants have not been fully understood to date. Endogenous BRs in plant tissue are extremely low and the elucidation of BRs functions relies on sensitive detection method. Reported methods for the determination of BRs required large amount of plant tissue, tedious pretreatment process, and were lack of selectivity. Therefore, development of a simple and selective method for the sensitive quantification of BRs is highly needed. RESULTS: We established a pretreatment method of BRs in plant tissues by employing double layered solid phase extraction (DL/SPE) combined with boronate affinity polymer monolith microextraction (BA/PMME). After the initial depigmentation with DL/SPE cartridge, boronate affinity polymer BA/PMME was employed to selectively extract BRs from sample matrix. Uniquely, most sample matrix was successfully removed by BA monolith purification. Using this method, BRs was determined by liquid chromatography-mass spectrometry (LC-MS). Endogenous active BRs could be detected in only 1 g fresh weigh (FW) leaves or 0.5 g FW flower tissues. CONCLUSION: A DL/SPE-BA/PMME pretreatment method for the determination of endogenous brassinosteroids in plant tissues was developed and validated. The proposed method was sensitive and selective. The proposed method may be further developed for the determination of other BRs including their precursors and conjugates.
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[Estimation of individual pharmacokinetic parameters using maximum a posteriori Bayesian method with D-optimal sampling strategy].
Yao Xue Xue Bao
PUBLISHED: 12-21-2011
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This study was aimed to develop a maximum a posteriori Bayesian (MAPB) estimation method to estimate individual pharmacokinetic parameters based on D-optimal sampling strategy. Meanwhile, the performance of MAPB was compared with the multiple linear regression (MLR) method in terms of accuracy and precision. Pharmacokinetic study of pioglitazone was employed as the example case. The population pharmacokinetics was characterized by nonlinear mixed effects model (NONMEM). The sparse sampling strategy (1-4 points) was identified by D-optimal algorithm using WinPOPT software. The simulated data generated by Monte Carlo method were used to access the performance of MAPB and MLR. As the number of samples per subject decreased, the accuracy and precision of MAPB method tended to get worse. The estimation for CL and Vby MAPB using D-optimal two-point design had less bias with low inter-individual variability, and had more bias and imprecision with high residue variability. The estimation of AUC by MAPB using D-optimal 2 points design had similar accuracy and precision to MLR. However, MAPB estimation was better than MLR while adjusting the sampling time to one hour. Overall, the MAPB method had similar predictive performance as MLR, but MAPB could provide more pharmacokinetic information with higher sampling flexibility.
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[Emotional problems and parenting locus of control in children with anxiety disorders].
Zhongguo Dang Dai Er Ke Za Zhi
PUBLISHED: 12-17-2011
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To carry out a preliminary study on the emotional problems and parenting locus of control among children with anxiety disorders.
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[Controlling effect of coagulation and sedimentation on naidid in water treatment process].
Huan Jing Ke Xue
PUBLISHED: 12-15-2011
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To control naidid pollution in water treatment conducted by O3-BAC, the removal effects of coagulation and sedimentation to naidid were estimated by field sampling of water plant, jar test and simulation study. The results showed that both coagulation and sedimentation of water plant and jar test had obvious removal efficiency on naidids. In the former the mean population density of naidid was decreased from 0. 52 ind/m3 to 0.17 ind/m3, while in the later removal efficiency, which did not be influenced by operation condition of coagulation and sedimentation, reached nearly 100%. Drift migration of naidid from sediment to over-lying water were observed in simulation study and the drift efficiency could be influenced by both temperature and water flow. The drift efficiency of 20 degrees C was 18.5%, much higher than that of 30 degrees C and 10 degrees C. While the velocities of water flow were 2, 4 and 8 mm/s, the number of drifting naidid were 11, 25 and 39 ind respectively. Because of the existence of drift migration, the settlement in sedimentation tank does not mean the real remove of naidid and the thoroughly separating of naidid from water treatment process can only be realized by sludge discharge of sedimentation tank. The naidid removal efficiency of coagulation and sedimentation can be increased by optimizing sludge discharge and restraining drift migration of naidid in sedimentation tank.
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Rapid magnetic solid-phase extraction based on magnetic multiwalled carbon nanotubes for the determination of polycyclic aromatic hydrocarbons in edible oils.
J. Agric. Food Chem.
PUBLISHED: 11-29-2011
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In this study, magnetic multiwalled carbon nanotubes were fabricated by a simple method and applied to magnetic solid-phase extraction (MSPE) of eight heavy molecular weight polycyclic aromatic hydrocarbons (PAHs) including chrysene, benzo[a]anthracene, benzo[b]fluoranthene, benzo[k]fluoranthene, benzo[a]pyrene, indeno[1,2,3-cd]pyrene, dibenzo[a,h]anthracene and benzo[g,h,i]perylene from edible oil samples. Several parameters affecting the extraction efficiency were investigated, including the type and volume of desorption solvent, extraction and desorption time, washing solution and the amount of sorbent. Under the optimized conditions, a simple and effective method for the determination of PAHs in edible oils was developed by coupling with gas chromatography-mass spectrometry (GC-MS). The whole pretreatment process was rapid, and it can be accomplished within 10 min. The limits of quantitation for the target PAHs were found to be 0.34-2.9 ng/g. The recoveries in oil sample were in the range 87.8-122.3% with the RSDs less than 6.8% (intraday) and 9.6% (interday). This method was successfully applied to the analysis of PAHs in seven kinds of edible oils from local markets.
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JoVE Visualize is a tool created to match the last 5 years of PubMed publications to methods in JoVE's video library.

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In developing our video relationships, we compare around 5 million PubMed articles to our library of over 4,500 methods videos. In some cases the language used in the PubMed abstracts makes matching that content to a JoVE video difficult. In other cases, there happens not to be any content in our video library that is relevant to the topic of a given abstract. In these cases, our algorithms are trying their best to display videos with relevant content, which can sometimes result in matched videos with only a slight relation.